FIG. 8 shows the fuel lid device disclosed in Patent Document 1 listed below. In the disclosed structure, a fuel lid (hereinbelow, referred to as the lid) 14 is mounted to the body 31 of a vehicle 11 through a hinge 21 so as to be flush with the vehicle body 11 in a closed position and expose a fuel cap 37 of a refueling inlet in an open position. The lid 14 has a locking strip 23 and an abutting part 41 disposed on an inner side thereof. The vehicle body 31 has a locking system 35 and a rod-opening system 40 disposed therein. The locking system 35 is brought into engagement with the locking strip 23 to lock the lid 14 in the closed position. The locking system is unlocked by an unlocking operation through an opener in the vehicle. The rod-opening system 40 includes an opening rod 15, which is supported so as to get in and out and is biased in a protruding direction. In the rod-opening system 40 thus constructed, when the locking system 35 is unlocked for fuel supply, the opening rod 15 is projected from an retracting position, being brought into contact with the abutting part 41 under the biasing action, to push out the lid 14 in an opening direction by a certain amount (a degree to which e.g. a finger is allowed to be put in for an opening operation). When the lid 14 is closed, the opening rod 15 is retracted in a direction to reduce the protruding length against the biasing action.
When the lid is closed, the opening rod 15 applies a pushing force to a counterpart of the lid 14 through the abutting part 41 while the lid 14 is locked by the locking system. In this case, the lid 14 is urged to swing about a line 25 connecting between the locking strip 23 and the hinge 21 since the opening rod 15 is disposed at a lower position than the locking system 35. In order to deal with this problem, the disclosed structure is configured so that the lid 14 has an upper end configured to be brought into contact with a size-adjusting member 29 disposed on a receiving portion 28 of the vehicle body 31 to prevent the upper end from getting in the vehicle body than needed for arranging an outer side thereof close to the upper end flush with the outer side of the vehicle body.
On the other hand, Patent Document 2 listed below discloses a push-up device, which pushes out a lid in an opening direction through, e.g. the push rod of a push-push system when the lid is depressed and the application of the depressing force is stopped in such a state that the lid is unlocked from a locking system. The disclosed device includes a cylindrical bottomed holder, a sleeve coupled to an upper side of the holder, a push rod disposed in the holder so as to protrude through a through hole formed in an upper side of the sleeve, heart-shaped cam grooves formed in opposed lateral sides of the push rod, a spring member disposed in the holder so as to bias the push rod in a protruding direction, a pin supported in the holder so as to be swingable and cause both ends to follow the heart-shaped cam grooves, and a cover coupled to a leading end of the push rod protruding from the sleeve.
The push-push system is configured so that the push rod is held in a retracted position having a protruding length reduced by the relationship between the pin and the heart-shaped cam grooves, and that when the push rod is released from being held by depressing the push rod through the lid, the push rod is switched to a protruding position having a protruding length increased by the biasing force of the spring member. Specifically, when the lid is closed, the push rod is set in the retracted position, and when the push rod is depressed through the lid, the push rod is released from being held in the retracted position with the result that the lid is pushed out by an action that is caused when the push rod is switched to the protruding position.
Patent Document 1: JP-A-2004-106584
Patent Document 2: DE-A-19650594